Help! Airbrush Disaster!

Ok, first time airbrushing on buttercream...and I'm using red. I know, I know...I thought I did all of my research. But I think I must have went too heavy or sprayed too close. First coat looked awesome. Second coat looked mottled and blotchy. Then I noticed the runs. So, I thought, I'll just blot the runs with paper towels and then respray. Now it's VERY mottled and blotchy. I've let it dry, can I just keep layering to at least make the blotchyness more subtle? Or scrape off the frosting, and re-ice with red frosting? Did I mention it's due tomorrow?? Thanks for any help! Trish